Device for measuring temperature in molten metals

Abstract

A device is provided for temperature measurement in metal melts, particularly in iron or steel melts, having a thermoelement, which is arranged in a thermoelement tube, and having an exterior protective body, which is essentially formed of graphite and metal oxide. The thermoelement tube is arranged in the protective body with a spacing, forming an intermediate space, and an insulating material and an oxygen-reducing material are arranged in the intermediate space. The insulating material and the oxygen-reducing material, as a powder mixture, form a tube ( 2 ), which surrounds the thermoelement tube ( 3 ) with a spacing and/or which is surrounded by the protective body ( 1 ) with a spacing.

1. A device for temperature measurement in metal melts, the device comprising a thermoelement arranged in a thermoelement tube, an exterior protective body essentially formed of graphite and metal oxide, the thermoelement tube being arranged with a spacing in the protective body, thereby forming an intermediate space between the tube and the body, and an insulating material and an oxygen-reducing material arranged in the intermediate space, the insulating material and the oxygen-reducing material being in a form of a powder mixture that forms a tube ( 2 ;  2 ′;  2 ″), which surrounds the thermoelement tube ( 3 ) with a spacing, and/or which is surrounded by the protective body ( 1 ) with a spacing. 
     
     
       2. The device according to  claim 1 , wherein the tube ( 2 ;  2 ′;  2 ″) is closed on one end, open at both ends, or is formed as a plurality of tube segments. 
     
     
       3. The device according to  claim 1 , wherein the powder mixture of the tube ( 2 ;  2 ′;  2 ″) includes a binder. 
     
     
       4. The device according to  claim 1 , wherein the device is designed for temperature measurement in iron or steel melts. 
     
     
       5. A method for producing a device according to  claim 1 , comprising forming a tube from the powder mixture, inserting the thermoelement ( 3 ) into the powder mixture tube, and arranging the protective body ( 1 ) around the powder mixture tube. 
     
     
       6. The device according to  claim 1 , wherein the insulating material comprises an oxide, and the oxygen-reducing material comprises a base metal. 
     
     
       7. The device according to  claim 6 , wherein the insulating material comprises aluminum oxide, and the base metal comprises aluminum. 
     
     
       8. The device according to  claim 7 , wherein the aluminum content, in reference to the powder mixture, ranges from 10 to 40 wt. %. 
     
     
       9. The device according to  claim 8 , wherein the aluminum content, in reference to the powder mixture, ranges from 15 to 33 wt. %. 
     
     
       10. The device according to  claim 1 , wherein the spacing between the powder mixture tube ( 2 ;  2 ′;  2 ″), on the one hand, and the thermoelement tube ( 3 ) or the protective body ( 1 ), on the other hand, is at least partially filled with gas, fibers, or balls. 
     
     
       11. The device according to  claim 10 , wherein the gas is a gas mixture. 
     
     
       12. The device according to  claim 11 , wherein the gas comprises nitrogen. 
     
     
       13. The device according to  claim 10 , wherein the fibers or balls are formed of aluminum oxide or of a mixture of an oxide and an oxygen-reducing material. 
     
     
       14. The device according to  claim 13 , wherein the fibers or balls are formed of aluminum oxide or of a mixture of aluminum oxide and a base metal. 
     
     
       15. The device according to  claim 14 , wherein the base metal comprises aluminum.